TI 59 Diagnostic Card Listing

[Sylvain Cote]

To cleanup my magnetic cards used in HP calculators (65/67/97/41/71/75), I use a:

1) Staedtler Mars Plastic Premium Eraser to remove the oxidation on the magnetic side, then
2) rub the same side with isopropyl 99.9% alcool

Most of the time (90+%) the card is working perfectly after the cleanup.

You have to be very careful to not pinch the card while using the eraser.
After pinching some cards, I have build a cleanup-jig to prevent that and I have not lost any card since then.

Sylvain